On Thu, 28 Jul 2011 12:04:37 -0700, Dale Miller wrote: >2) There is a difference between the relative priority of DCB >information, and the actual mechanism involved. The order of priority >was stated correctly,
stated correctly by whom? AFAIK, CM Poncelet got it wrong. >but the exact mechanism is a little more complex >and does depend on > a) whether the DISP is NEW (or MOD if the dataset is not found and >must be created), or OLD/SHR(or MOD if the dataset is found) Label (DSCB or tape label) is only used for an existing data set > b) whether the file is opened for INPUT or OUTPUT. Mr. Poncelet made the same assertion. I'm pretty sure that it is incorrect. Do you have a manual reference that you can cite to justify it? >one can >TEMPORARILY override the dataset attributes with a DD card if the OPEN >is for INPUT No. See for example the JCL Reference manual. <quote> 12.16.3 Completing the Data Control Block The system obtains data control block information from the following sources, in override order: - The processing program, that is, the DCB macro instruction in assembler language programs or file definition statements or language-defined defaults in programs in other languages. - The DCB subparameter of the DD statement. - The data set label. Therefore, if you supply information for the same DCB field in your processing program and on a DD statement, the system ignores the DD DCB subparameter. If a DD statement and the data set label supply information for the same DCB field, the system ignores the data set label information. </quote> -- Tom Marchant ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
